192.168.100.100 Admin Login

ZTE routers and Grandstream analog telephone adapters (ATAs) are among the known network devices that use 192.168.100.100 as their default IP address. It is a Class C private IPv4 address belonging to the 192.168.100.0/24 subnet — a range commonly deployed in business, ISP-provisioned, and SOHO (Small Office/Home Office) environments. Unlike the more widely recognized 192.168.1.1 or 192.168.0.1, the 192.168.100.x subnet is often chosen by manufacturers and ISPs to reduce the chance of IP conflicts with other devices on bridged or multi-router networks. Only one device on your local network should be assigned 192.168.100.100 at any given time to avoid address conflicts. Other commonly used default gateways in related subnets include 192.168.100.1 and 192.168.8.1.

How to Access 192.168.100.100

To reach your device's admin panel, open any web browser and type http://192.168.100.100 directly into the address bar — do not use the search bar. Press Enter and you should be presented with a login page. This works for ZTE routers, Grandstream HT-series ATAs, and any other network device configured to use 192.168.100.100 as its management interface address.

Before you can access the panel, your computer or device must be connected to the same network. You can connect via:

• Ethernet cable — plug a LAN cable from your PC into one of the router's LAN ports (not the WAN port).
• Wi-Fi — connect to the wireless network broadcast by the device.

Once connected, navigate to http://192.168.100.100 and enter your login credentials. For most ZTE devices, the default username is admin and the default password is admin. For Grandstream ATAs, the default admin password is typically admin as well. Always check the label on the back or bottom of your device for the exact factory credentials, as ISP-provisioned units may have customized defaults.

After logging in, you can manage settings such as your Wi-Fi network name (SSID), wireless password, DHCP configuration, port forwarding, parental controls, and firmware updates — all from within the admin panel at 192.168.100.100.

If You Can't Access 192.168.100.100

If typing http://192.168.100.100 into your browser returns an error like "This site can't be reached" or the page simply times out, there are several possible causes to investigate:

• Wrong gateway address: 192.168.100.100 may not be the default IP for your specific device. Open the Command Prompt (Windows: press Win + R, type cmd, press Enter) and run ipconfig /all. Look for the Default Gateway field — that is the correct IP to use. On macOS, go to System Settings > Network > Details and check the Router field.
• Wrong port connection: Make sure your Ethernet cable is plugged into a LAN port, not the WAN/Internet port. The WAN port is for your incoming internet line, not for admin access.
• IP address conflict: If another device on your network has been manually assigned 192.168.100.100, a conflict will prevent access. Check your connected devices and reassign any conflicting static IPs.
• Typing error: Ensure you are entering http://192.168.100.100 — not https://, not http//, and not using the search bar. The address must go into the browser's URL/address bar.
• Browser cache issue: Try a different browser or open an incognito/private window to rule out cached redirects.

If none of the above resolves the issue, check our guide to find your router IP address for a step-by-step walkthrough.

Default Username and Password for 192.168.100.100

When you first access the admin panel at 192.168.100.100, you'll need to enter the factory default credentials. The most common combinations for devices using this IP are listed below. If your device is ISP-provisioned (e.g., a ZTE fiber modem supplied by your internet provider), the credentials may have been customized — always check the sticker on the device first.

• Username: admin | Password: admin
• Username: admin | Password: password
• Username: admin | Password: 1234
• Username: admin | Password: (blank — leave empty)

For Grandstream HT80x and HT81x series ATAs, the default admin password is admin, and there is no username required on some firmware versions — you simply enter the password on the login screen. The viewer-level password is typically 123.

It is strongly recommended that you change the default password immediately after your first login. Leaving factory credentials in place is a significant security risk, as these combinations are publicly documented and widely known.

Changing Your Router's Password at 192.168.100.100

Securing your network starts with changing the default admin password on your device. Once you have logged into the admin panel at http://192.168.100.100, follow these general steps:

1. Navigate to the Administration, System, or Management section of the interface — the exact label depends on your device's firmware.
2. Look for a Change Password, Admin Password, or User Management option.
3. Enter your current password, then type your new password twice to confirm.
4. Click Save or Apply to commit the change.

For ZTE routers using 192.168.100.100, the password change option is typically found under Maintenance > Account Management. For Grandstream ATAs, navigate to the Basic Settings tab and locate the Admin Password field.

A strong password should be at least 12 characters long and include a mix of uppercase letters, lowercase letters, numbers, and symbols. Avoid using easily guessable information such as your address, name, or the word "password." You should also consider changing your Wi-Fi SSID and wireless password while you're in the admin panel, so your network name doesn't reveal the router brand to potential attackers.

Router Username and Password List

Router Brands That Use 192.168.100.100

While 192.168.100.100 is not as universally common as 192.168.1.1 or 192.168.0.1, it is the confirmed default management IP for specific product lines from the following manufacturers:

• ZTE — ZTE uses 192.168.100.100 across several of its DSL modem-router and fiber ONT (Optical Network Terminal) product lines. ZTE devices are widely deployed by ISPs globally, particularly in Asia, Africa, and Latin America. Models such as the ZTE F660, F670, and ZXHN series may use this address depending on the firmware and ISP configuration.
• Grandstream — Grandstream's HT800 and HT810 series Analog Telephone Adapters (ATAs), including the HT801, HT802, HT812, and HT814, use 192.168.100.100 as the default static IP address for their management interface. This is specifically the default for the device's Management VLAN interface when configured with a static IP.

If your device is not from ZTE or Grandstream but is still resolving to 192.168.100.100, it may have been manually configured by a network administrator or ISP technician to use this address within the 192.168.100.0/24 subnet. In enterprise and ISP environments, the 192.168.100.x range is frequently chosen to avoid overlap with the more common 192.168.1.x and 192.168.0.x home network ranges.

How to Factory Reset a Device Using 192.168.100.100

If you've forgotten your admin password or your device is behaving unexpectedly, a factory reset will restore it to its original settings — including the default IP address of 192.168.100.100, the default username, and the default password. Warning: A factory reset will erase all custom configurations, including your Wi-Fi name, password, port forwarding rules, and any ISP-specific settings. Make sure you have your ISP login credentials (PPPoE username/password) on hand before proceeding.

Hardware Reset (Physical Reset Button)

1. Locate the Reset button on your device. On most ZTE routers, it is a small recessed button on the back or bottom panel, labeled "RESET."
2. With the device powered on, use a straightened paperclip, pin, or similar pointed object to press and hold the Reset button.
3. Hold for 10–15 seconds until the indicator LEDs flash or change color, signaling that the reset has been initiated.
4. Release the button and wait for the device to fully reboot — this typically takes 60–90 seconds.
5. Once rebooted, the device will be accessible again at http://192.168.100.100 with factory default credentials.

Software Reset (Via Admin Panel)

1. Log in to the admin panel at http://192.168.100.100.
2. Navigate to Maintenance, Administration, or System Tools depending on your device's interface.
3. Select Factory Reset, Restore Default Settings, or a similarly labeled option.
4. Confirm the action when prompted. The device will reboot automatically and return to factory defaults.

For Grandstream ATAs, you can also perform a reset by dialing * * * 99 on a connected analog phone, which triggers a factory reset via the IVR menu.

What Is 192.168.100.100? Understanding This Private IP Address

192.168.100.100 is a Class C private IPv4 address defined under RFC 1918. This means it is reserved exclusively for use within private networks and is not routable on the public internet. No data sent to or from 192.168.100.100 will ever travel beyond your local network without being translated by NAT (Network Address Translation) on your router.

The address belongs to the 192.168.100.0/24 subnet, which provides a range of 254 usable host addresses: from 192.168.100.1 to 192.168.100.254. The address 192.168.100.0 is the network address and 192.168.100.255 is the broadcast address — neither can be assigned to a device.

What makes 192.168.100.100 somewhat unusual compared to typical default gateways is that it sits in the middle of the subnet rather than at the low end (like .1 or .2). This is a deliberate design choice by manufacturers like ZTE and Grandstream — by placing the management IP at .100, the lower addresses (192.168.100.1 through 192.168.100.99) remain available for DHCP assignment to client devices without conflicting with the management interface.

In terms of network hierarchy, 192.168.100.100 functions as follows:

• Network Address: 192.168.100.0
• Subnet Mask: 255.255.255.0 (/24)
• Default Gateway (typical): 192.168.100.1
• Management IP: 192.168.100.100
• Broadcast Address: 192.168.100.255
• Usable Host Range: 192.168.100.1 – 192.168.100.254

The 192.168.100.x subnet is also popular in enterprise and ISP deployments because it is less likely to conflict with the default subnets used by home routers (192.168.0.x and 192.168.1.x). This makes it a practical choice when connecting multiple routers or when an ISP-supplied modem needs to coexist with a customer's own router without causing double-NAT issues.

Related IP Addresses in the 192.168.100.0/24 Subnet

The 192.168.100.0/24 subnet contains several IP addresses that are commonly used as default gateways or management interfaces by various network devices. If 192.168.100.100 is not the correct address for your device, one of the following may be:

• 192.168.100.1 — The most common default gateway in the 192.168.100.x subnet, used by Huawei modems and various ISP-provisioned devices as the primary router gateway address.
• 192.168.100.2 — Sometimes used as a secondary management address or assigned to a secondary device in the subnet.
• 192.168.100.254 — Used by some DSL modems and managed switches as an alternative management IP at the high end of the subnet.

Other commonly referenced default gateway addresses outside this subnet that you may encounter include 192.168.1.254, 192.168.2.1, 192.168.10.1, and 10.0.0.1.

Frequently Asked Questions About 192.168.100.100

What is 192.168.100.100 used for?

192.168.100.100 is used as the default management IP address for certain network devices, most notably ZTE routers and Grandstream ATA devices. Typing this address into your browser gives you access to the device's admin panel, where you can configure Wi-Fi settings, change passwords, set up port forwarding, and more.

Is 192.168.100.100 the same as my router's gateway?

Not necessarily. While 192.168.100.100 is the management interface IP for some devices (particularly Grandstream ATAs), the actual default gateway in the 192.168.100.x subnet is more commonly 192.168.100.1. On ZTE routers, 192.168.100.100 may serve as both the management IP and the gateway depending on the model and ISP configuration. Run ipconfig /all on Windows or check your network settings to confirm your actual gateway.

Why can't I log in to 192.168.100.100?

The most common reasons are: (1) your device's IP has been changed from the factory default, (2) you are not connected to the correct network, (3) you are entering the address in the search bar instead of the browser's URL bar, or (4) there is an IP conflict on your network. Try connecting via Ethernet cable directly to a LAN port and re-entering http://192.168.100.100 in the address bar.

What is the default password for 192.168.100.100?

For ZTE devices using 192.168.100.100, the most common default credentials are username admin and password admin. For Grandstream ATAs, the default admin password is admin with no username required on some models. Always check the label on your device, as ISP-provisioned units may use custom credentials.

How do I reset my device back to 192.168.100.100?

If the IP address has been changed and you want to restore it to 192.168.100.100, perform a factory reset by pressing and holding the Reset button on the back of your device for 10–15 seconds while it is powered on. After the device reboots, it will return to its factory default settings, including the 192.168.100.100 address.

Is 192.168.100.100 safe to use?

Yes — 192.168.100.100 is a private IP address and is completely safe. It cannot be accessed from the internet, only from devices within your local network. However, you should always change the default admin password after logging in to prevent unauthorized access from within your network.

Can two devices share the IP 192.168.100.100?

No. Just like any IP address, 192.168.100.100 must be unique within your network. If two devices are assigned the same IP, an address conflict will occur, causing connectivity issues for both devices. Ensure only one device uses this address at a time.